In a biochemical automatic analysis apparatus, trace quantification is proceeded in the long term, and quantitativity and reproducibility are required as well. In addition, in a biochemical analysis device, as a technique for dispensing a specimen or reagent, a dispensation technique of sucking or discharging a predetermined fluid by using a syringe pump is widely employed, in general. A highly accurate dispensation technique is the most important element technique in order to realize quantitativity and reproducibility in trace dispensation.
In a dispensing device, a valve for controlling a direction of a fluid is provided between a nozzle for discharging liquid and a syringe pump in many cases, and with this fluid control valve, a complicated flow path configuration is possible. In such a dispensation mechanism, there is a case where, during dispensation operation of repeatedly performing suction of a fluid, bubbles are adhered to a fluid control inner wall accommodating a fluid or an irregular portion connected to a flow path. If trace dispensation is carried out while there are adhered bubbles, the internal pressure of a flow path fluctuates as a result of variation in the volume of the bubbles, and the amount of liquid to be dispensed becomes inconsistent, and thus there is a problem that dispensing accuracy decreases.
For this reason, removing bubbles by providing a special mechanism in a dispensing device is carried out. For example, as in PTL 1, an invention provided with a vibration mechanism for removing bubbles in a dispensing device is known.